Compression numbers?
#1
Compression numbers?
Hello. I may have blown a headgasket and I am current trying to track it down. My compression numbers are as follows..
back of the motor
190 190
170 175
190 187
Front of the motor
This was all prompted by white smoke coming from the exhaust... Any thoughts as to why the middle two are so inconsistant? The test was done dry and a leakdown is up next... In the meantime please feel free to chime in. Many thanks.
Kevin
back of the motor
190 190
170 175
190 187
Front of the motor
This was all prompted by white smoke coming from the exhaust... Any thoughts as to why the middle two are so inconsistant? The test was done dry and a leakdown is up next... In the meantime please feel free to chime in. Many thanks.
Kevin
Last edited by Sicarius428; Jul 31, 2010 at 01:51 PM.
#5
Your numbers are within specs but 20 psi is too much between cyl's. The leakdown is okay? they all held pressure? Here's the FSM link for the compression test.
http://www.ncttora.com/fsm/1996/SIL/...compr/insp.pdf
http://www.ncttora.com/fsm/1996/SIL/...compr/insp.pdf
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#8
Redid the compression test.
Back of block
190 190
185 185
190 187
Front of block
Dunno what changed... but the numbers look better at least. Any thoughts as to why I am getting white smoke/coolant out the exhaust?
Kevin
Back of block
190 190
185 185
190 187
Front of block
Dunno what changed... but the numbers look better at least. Any thoughts as to why I am getting white smoke/coolant out the exhaust?
Kevin
#13
Is the truck 5spd? if so did you loose 5th gear on the freeway? Mine started to loose power. Have you been watching your coolant level? pressure test the coolant system with the plugs pulled out over night.
#14
It's an automatic.
Little history on my situation... My original motor was tired 200k and the shims in the head were waaaay out of spec. So much that toyota didn't sell ones large enough. So I found a replacement motor and swapped them. Unknown history about the replacement but I picked it up for 500 bucks... Heads are in spec so worse case I can pull the heads and swap them to my original tired block but since I have the motor in the truck now, I would like to do my due diligence and try to make this one work. The motor had the newer exhaust manifolds so I knew that it couldn't have too many miles on it. Compression suggests so too but just trying to track down where the water is coming from. I havn't actually been able to run the truck to find out how much water is going other than what my driveway would be able to tell. If I goose the gas there is a decent ploom of water vapor coming out the exhaust and the motor is at temp so it's not part of the warmup.
Pressure test. Great idea. I will do that. Thanks again for all the support on this!
Kevin
Little history on my situation... My original motor was tired 200k and the shims in the head were waaaay out of spec. So much that toyota didn't sell ones large enough. So I found a replacement motor and swapped them. Unknown history about the replacement but I picked it up for 500 bucks... Heads are in spec so worse case I can pull the heads and swap them to my original tired block but since I have the motor in the truck now, I would like to do my due diligence and try to make this one work. The motor had the newer exhaust manifolds so I knew that it couldn't have too many miles on it. Compression suggests so too but just trying to track down where the water is coming from. I havn't actually been able to run the truck to find out how much water is going other than what my driveway would be able to tell. If I goose the gas there is a decent ploom of water vapor coming out the exhaust and the motor is at temp so it's not part of the warmup.
Pressure test. Great idea. I will do that. Thanks again for all the support on this!
Kevin
Last edited by Sicarius428; Aug 1, 2010 at 11:34 PM.
#15
OK. Finally got around to getting a coolant system pressure checker and it is definately loosing pressure. The other weekend I let it idle in the driveway for a few hours. Coolant level didn't seem to move though... Looking down the spark plug holes. The pistons don'[t look "washed" like how my 5.0 was when the headgasket went on it. The spark plugs still look new.... Any suggestions?
Kevin
Kevin
#16
best to check by taking the spark plugs out and using the cooling system pressure checker to pressure the system then let it sit over night and see if any of the pistons have water in them. thats how we do it at the shop when we get a hint of blown head gasket.
#18
I assume you checked for milkshake in your oil. x3 on letting it sit with the pressure tester overnight w/o plugs.
Edit: A minute too late
Doesn't sound like a HG.
Edit: A minute too late
Doesn't sound like a HG.
Last edited by brian2sun; Aug 29, 2010 at 03:10 PM.
#20
Could be intake mani gasket. Also check your ATF fluid to make sure it's not strawberry milkshake. How does the coolant look? Might as well check the PCV and tubing too because it's easy (the valve should rattle when you shake it). Are you sure it's not steam from the cat and not white smoke?


